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61.
Analysis of RC slab–beam–column sub‐assemblages subjected to bidirectional lateral cyclic loading using a new 3D macroelement
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An existing two‐dimensional macroelement for reinforced concrete beam–column joints is extended to a three‐dimensional macroelement. The three‐dimensional macroelement for beam–column joints consists of six rigid interface plates and uniaxial springs for concrete, steel, and bond–slip, which model the inside of a beam–column joint. The mechanical models for the materials and the stiffness equation for the springs are also presented. To validate the model, we used test results from three slab–beam–column sub‐assemblages subjected to bi‐lateral cyclic load. It is revealed that the new joint model is capable of capturing the strength of beam–column joints and the bidirectional interaction in joint shear response, including the concentration of damage in the beam–column joint, the pinching nature in hysteretic behavior, the stiffness degradation, and strength deterioration resulting from cyclic and bidirectional loading. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
62.
Masayuki Uesugi Motoo Ito Hikaru Yabuta Hiroshi Naraoka Fumio Kitajima Yoshinori Takano Hajime Mita Yoko Kebukawa Aiko Nakato Yuzuru Karouji 《Meteoritics & planetary science》2019,54(3):638-666
Carbonaceous materials in the sample catcher of the Hayabusa spacecraft were assigned as category 3 particles. We investigated the category 3 particles with a suite of in situ microanalytical methods. Possible contaminants collected from the cleanrooms of the spacecraft assembly and extraterrestrial sample curation center (ESCuC) were also analyzed in the same manner as category 3 particles for comparison. Our data were integrated with those of the preliminary examination team for category 3 particles. Possible origins for the category 3 particles include contamination before and after the operation of the Hayabusa spacecraft. 相似文献
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64.
Mohsen Ahadnejad Yoshihisa Maruyama Fumio Yamazaki 《Journal of the Indian Society of Remote Sensing》2009,37(4):659-669
Land use and land cover changes due to human activities in a time sequence. Detection of such changes may help decision makers
and planners to understand the factors in land use and land cover change in order to take effective and useful measures. Remote
sensing and GIS techniques may be used as efficient tools to detect and assess land use change. 相似文献
65.
Recently carbon dioxide fluxes between sea water and air have been measured in many coastal seas to clarify whether the coastal seas are source or sink of CO2. In this study behavior of CO2 within the water column was studied in a semi-enclosed coastal sea: the Seto Inland Sea, Japan. It was found that seasonal formation of hypoxic water mass is highly related to CO2 dynamics in coastal seas. Bacterial remineralization of organic matter consumes dissolved oxygen (DO) and releases dissolved CO2 in the bottom water when summertime thermal stratification develops. The CO2 accumulates within the low DO bottom water (hypoxic water) and causes increasing of carbonic acid content which results in low pH. Concentrations of dissolved CO2 and pH are highly correlated with DO concentration. The summertime low DO and acidification (low pH) occur in the lower layer every year. The accumulated CO2 during the summer season is dispersed to the atmosphere at the beginning of mixing season. 相似文献
66.
SIMS Bias on Isotope Ratios in Ca‐Mg‐Fe Carbonates (Part III): δ18O and δ13C Matrix Effects Along the Magnesite–Siderite Solid‐Solution Series
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Maciej G. Śliwiński Kouki Kitajima Michael J. Spicuzza Ian J. Orland Akizumi Ishida John H. Fournelle John W. Valley 《Geostandards and Geoanalytical Research》2018,42(1):49-76
This study explores the effects of cation composition on mass bias (i.e., the matrix effect), which is a major component of instrumental mass fractionation (IMF) in the microanalyses of δ13C and δ18O by SIMS in carbonates of the magnesite–siderite solid‐solution series (MgCO3–FeCO3). A suite of twelve calibration reference materials (RMs) was developed and documented (calibrated range: Fe# = 0.002–0.997, where Fe# = molar Fe/[Mg + Fe]), along with empirical expressions for regressing calibration data (affording residuals < 0.5‰ relative to certified reference material NIST‐19). The calibration curves of both isotope systems are non‐linear and have, over a 2‐year period, fallen into one of two distinct but largely self‐consistent shape categories (data from ten measurement sessions), despite adherence to well‐established analytical protocols for carbonate δ13C and δ18O analyses at WiscSIMS (CAMECA IMS 1280). Mass bias was consistently most sensitive to changes in composition near the magnesite end‐member (Fe# 0–0.2), deviating by up to 4.5‰ (δ13C) and 14‰ (δ18O) with increasing Fe content. The cause of variability in calibration curve shapes is not well understood at present and demonstrates the importance of having available a sufficient number of well‐characterised RMs so that potential complexities of curvature can be adequately delineated and accounted for on a session‐by‐session basis. 相似文献
67.
68.
Culture-dependent and independent analyses of subsurface microbial communities in oil-bearing strata of the Sagara oil reservoir 总被引:3,自引:0,他引:3
Takuro Nunoura Hanako Oida Noriaki Masui Fumio Inagaki Ken Takai Satoshi Hirano Kenneth H. Nealson Koki Horikoshi 《Island Arc》2006,15(3):328-337
Abstract Culture-dependent and independent methods were used to evaluate the microbial communities in cores collected at depths up to 200 m in oil-bearing and oil-free strata near the Sagara oil reservoir near Shizuoka, Japan. Direct microbial counts revealed much higher numbers (2.2 × 104 −7.9 × 106 /g) of microbes in the oil-bearing strata than in the oil-free zones, where counts were uniform at approximately 1.0 × 104 /g. Molecular taxonomic analyses via 16S rRNA gene sequence comparisons showed that the oil-free strata were dominated by members of the γ-Proteobacteria including Pseudomonas , Stenotrophomonas and Sphingomonas , whereas the oil-bearing strata were dominated by a single species closely related to Pseudomonas stutzeri . All archaeal clones were phylogenetically affiliated with the uncultured soil group in Crenarchaeota with the exception of a single phylotype that belonged to the genus Thermococcus . Culture-dependent analysis was carried out by most-probable-number culturing as well as direct plating to determine viable cell counts, using both complex organic substrates or native oil and autotrophic media. Both culture-dependent and independent methods revealed the abundant cultivable member was the aerobic oil-degrading bacterium Pseudomonas stutzeri and neither autotrophs nor anaerobic heterotrophs could be detected in the oil-bearing strata. 相似文献
69.
70.
Yalkun Yusuf Masashi Matsuoka Fumio Yamazaki 《Journal of the Indian Society of Remote Sensing》2001,29(1-2):17-22
In this paper, we present a method of earthquake damage detection by comparing the optical images with panchromatic bands for the Gujarat, India earthquake, which occurred on January 26, 2001. The data used in this study are optical remote sensing images taken by Landsat-7 satellite on January 8 and February 29, 2001, before and after the earthquake. We have investigated the pre and post-earthquake satellite images calculating the differences in the reflection intensity (digital number) of the two images. The estimated affected area has been subtracted on a pixel unit based on the obtained frequency distributions of the differences in the optical sensor values, which show significant changes in the reflectance due to the earthquake disaster. We have investigated the accuracy of our analysis result using a classification method for the training areas with aerial photographs taken after the earthquake. The two damage detection methods show a very similar result. 相似文献